bytecodegenerator.cpp

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    emitOpcode(op_resolve_base);
    instructions().append(dst->index());
    instructions().append(addConstant(property));
    return dst;
}

RegisterID* BytecodeGenerator::emitResolveWithBase(RegisterID* baseDst, RegisterID* propDst, const Identifier& property)
{
    emitOpcode(op_resolve_with_base);
    instructions().append(baseDst->index());
    instructions().append(propDst->index());
    instructions().append(addConstant(property));
    return baseDst;
}

RegisterID* BytecodeGenerator::emitResolveFunction(RegisterID* baseDst, RegisterID* funcDst, const Identifier& property)
{
    emitOpcode(op_resolve_func);
    instructions().append(baseDst->index());
    instructions().append(funcDst->index());
    instructions().append(addConstant(property));
    return baseDst;
}

RegisterID* BytecodeGenerator::emitGetById(RegisterID* dst, RegisterID* base, const Identifier& property)
{
#if ENABLE(JIT)
    m_codeBlock->addStructureStubInfo(StructureStubInfo(op_get_by_id));
#else
    m_codeBlock->addPropertyAccessInstruction(instructions().size());
#endif

    emitOpcode(op_get_by_id);
    instructions().append(dst->index());
    instructions().append(base->index());
    instructions().append(addConstant(property));
    instructions().append(0);
    instructions().append(0);
    instructions().append(0);
    instructions().append(0);
    return dst;
}

RegisterID* BytecodeGenerator::emitPutById(RegisterID* base, const Identifier& property, RegisterID* value)
{
#if ENABLE(JIT)
    m_codeBlock->addStructureStubInfo(StructureStubInfo(op_put_by_id));
#else
    m_codeBlock->addPropertyAccessInstruction(instructions().size());
#endif

    emitOpcode(op_put_by_id);
    instructions().append(base->index());
    instructions().append(addConstant(property));
    instructions().append(value->index());
    instructions().append(0);
    instructions().append(0);
    instructions().append(0);
    instructions().append(0);
    return value;
}

RegisterID* BytecodeGenerator::emitPutGetter(RegisterID* base, const Identifier& property, RegisterID* value)
{
    emitOpcode(op_put_getter);
    instructions().append(base->index());
    instructions().append(addConstant(property));
    instructions().append(value->index());
    return value;
}

RegisterID* BytecodeGenerator::emitPutSetter(RegisterID* base, const Identifier& property, RegisterID* value)
{
    emitOpcode(op_put_setter);
    instructions().append(base->index());
    instructions().append(addConstant(property));
    instructions().append(value->index());
    return value;
}

RegisterID* BytecodeGenerator::emitDeleteById(RegisterID* dst, RegisterID* base, const Identifier& property)
{
    emitOpcode(op_del_by_id);
    instructions().append(dst->index());
    instructions().append(base->index());
    instructions().append(addConstant(property));
    return dst;
}

RegisterID* BytecodeGenerator::emitGetByVal(RegisterID* dst, RegisterID* base, RegisterID* property)
{
    emitOpcode(op_get_by_val);
    instructions().append(dst->index());
    instructions().append(base->index());
    instructions().append(property->index());
    return dst;
}

RegisterID* BytecodeGenerator::emitPutByVal(RegisterID* base, RegisterID* property, RegisterID* value)
{
    emitOpcode(op_put_by_val);
    instructions().append(base->index());
    instructions().append(property->index());
    instructions().append(value->index());
    return value;
}

RegisterID* BytecodeGenerator::emitDeleteByVal(RegisterID* dst, RegisterID* base, RegisterID* property)
{
    emitOpcode(op_del_by_val);
    instructions().append(dst->index());
    instructions().append(base->index());
    instructions().append(property->index());
    return dst;
}

RegisterID* BytecodeGenerator::emitPutByIndex(RegisterID* base, unsigned index, RegisterID* value)
{
    emitOpcode(op_put_by_index);
    instructions().append(base->index());
    instructions().append(index);
    instructions().append(value->index());
    return value;
}

RegisterID* BytecodeGenerator::emitNewObject(RegisterID* dst)
{
    emitOpcode(op_new_object);
    instructions().append(dst->index());
    return dst;
}

RegisterID* BytecodeGenerator::emitNewArray(RegisterID* dst, ElementNode* elements)
{
    Vector<RefPtr<RegisterID>, 16> argv;
    for (ElementNode* n = elements; n; n = n->next()) {
        if (n->elision())
            break;
        argv.append(newTemporary());
        // op_new_array requires the initial values to be a sequential range of registers
        ASSERT(argv.size() == 1 || argv[argv.size() - 1]->index() == argv[argv.size() - 2]->index() + 1);
        emitNode(argv.last().get(), n->value());
    }
    emitOpcode(op_new_array);
    instructions().append(dst->index());
    instructions().append(argv.size() ? argv[0]->index() : 0); // argv
    instructions().append(argv.size()); // argc
    return dst;
}

RegisterID* BytecodeGenerator::emitNewFunction(RegisterID* dst, FuncDeclNode* n)
{
    emitOpcode(op_new_func);
    instructions().append(dst->index());
    instructions().append(addConstant(n));
    return dst;
}

RegisterID* BytecodeGenerator::emitNewRegExp(RegisterID* dst, RegExp* regExp)
{
    emitOpcode(op_new_regexp);
    instructions().append(dst->index());
    instructions().append(addRegExp(regExp));
    return dst;
}


RegisterID* BytecodeGenerator::emitNewFunctionExpression(RegisterID* r0, FuncExprNode* n)
{
    emitOpcode(op_new_func_exp);
    instructions().append(r0->index());
    instructions().append(addConstant(n));
    return r0;
}

RegisterID* BytecodeGenerator::emitCall(RegisterID* dst, RegisterID* func, RegisterID* thisRegister, ArgumentsNode* argumentsNode, unsigned divot, unsigned startOffset, unsigned endOffset)
{
    return emitCall(op_call, dst, func, thisRegister, argumentsNode, divot, startOffset, endOffset);
}

RegisterID* BytecodeGenerator::emitCallEval(RegisterID* dst, RegisterID* func, RegisterID* thisRegister, ArgumentsNode* argumentsNode, unsigned divot, unsigned startOffset, unsigned endOffset)
{
    return emitCall(op_call_eval, dst, func, thisRegister, argumentsNode, divot, startOffset, endOffset);
}

RegisterID* BytecodeGenerator::emitCall(OpcodeID opcodeID, RegisterID* dst, RegisterID* func, RegisterID* thisRegister, ArgumentsNode* argumentsNode, unsigned divot, unsigned startOffset, unsigned endOffset)
{
    ASSERT(opcodeID == op_call || opcodeID == op_call_eval);
    ASSERT(func->refCount());
    ASSERT(thisRegister->refCount());

    RegisterID* originalFunc = func;
    if (m_shouldEmitProfileHooks) {
        // If codegen decided to recycle func as this call's destination register,
        // we need to undo that optimization here so that func will still be around
        // for the sake of op_profile_did_call.
        if (dst == func) {
            RefPtr<RegisterID> movedThisRegister = emitMove(newTemporary(), thisRegister);
            RefPtr<RegisterID> movedFunc = emitMove(thisRegister, func);
            
            thisRegister = movedThisRegister.release().releaseRef();
            func = movedFunc.release().releaseRef();
        }
    }

    // Generate code for arguments.
    Vector<RefPtr<RegisterID>, 16> argv;
    argv.append(thisRegister);
    for (ArgumentListNode* n = argumentsNode->m_listNode.get(); n; n = n->m_next.get()) {
        argv.append(newTemporary());
        // op_call requires the arguments to be a sequential range of registers
        ASSERT(argv[argv.size() - 1]->index() == argv[argv.size() - 2]->index() + 1);
        emitNode(argv.last().get(), n);
    }

    // Reserve space for call frame.
    Vector<RefPtr<RegisterID>, RegisterFile::CallFrameHeaderSize> callFrame;
    for (int i = 0; i < RegisterFile::CallFrameHeaderSize; ++i)
        callFrame.append(newTemporary());

    if (m_shouldEmitProfileHooks) {
        emitOpcode(op_profile_will_call);
        instructions().append(func->index());

#if ENABLE(JIT)
        m_codeBlock->addFunctionRegisterInfo(instructions().size(), func->index());
#endif
    }

    emitExpressionInfo(divot, startOffset, endOffset);

#if ENABLE(JIT)
    m_codeBlock->addCallLinkInfo();
#endif

    // Emit call.
    emitOpcode(opcodeID);
    instructions().append(dst->index()); // dst
    instructions().append(func->index()); // func
    instructions().append(argv.size()); // argCount
    instructions().append(argv[0]->index() + argv.size() + RegisterFile::CallFrameHeaderSize); // registerOffset

    if (m_shouldEmitProfileHooks) {
        emitOpcode(op_profile_did_call);
        instructions().append(func->index());

        if (dst == originalFunc) {
            thisRegister->deref();
            func->deref();
        }
    }

    return dst;
}

RegisterID* BytecodeGenerator::emitReturn(RegisterID* src)
{
    if (m_codeBlock->needsFullScopeChain()) {
        emitOpcode(op_tear_off_activation);
        instructions().append(m_activationRegisterIndex);
    } else if (m_codeBlock->usesArguments() && m_codeBlock->m_numParameters > 1)
        emitOpcode(op_tear_off_arguments);

    return emitUnaryNoDstOp(op_ret, src);
}

RegisterID* BytecodeGenerator::emitUnaryNoDstOp(OpcodeID opcodeID, RegisterID* src)
{
    emitOpcode(opcodeID);
    instructions().append(src->index());
    return src;
}

RegisterID* BytecodeGenerator::emitConstruct(RegisterID* dst, RegisterID* func, ArgumentsNode* argumentsNode, unsigned divot, unsigned startOffset, unsigned endOffset)
{
    ASSERT(func->refCount());

    RegisterID* originalFunc = func;
    if (m_shouldEmitProfileHooks) {
        // If codegen decided to recycle func as this call's destination register,
        // we need to undo that optimization here so that func will still be around
        // for the sake of op_profile_did_call.
        if (dst == func) {
            RefPtr<RegisterID> movedFunc = emitMove(newTemporary(), func);
            func = movedFunc.release().releaseRef();
        }
    }

    RefPtr<RegisterID> funcProto = newTemporary();

    // Generate code for arguments.
    Vector<RefPtr<RegisterID>, 16> argv;
    argv.append(newTemporary()); // reserve space for "this"
    for (ArgumentListNode* n = argumentsNode ? argumentsNode->m_listNode.get() : 0; n; n = n->m_next.get()) {
        argv.append(newTemporary());
        // op_construct requires the arguments to be a sequential range of registers
        ASSERT(argv[argv.size() - 1]->index() == argv[argv.size() - 2]->index() + 1);
        emitNode(argv.last().get(), n);
    }

    if (m_shouldEmitProfileHooks) {
        emitOpcode(op_profile_will_call);
        instructions().append(func->index());
    }

    // Load prototype.
    emitExpressionInfo(divot, startOffset, endOffset);
    emitGetByIdExceptionInfo(op_construct);
    emitGetById(funcProto.get(), func, globalData()->propertyNames->prototype);

    // Reserve space for call frame.
    Vector<RefPtr<RegisterID>, RegisterFile::CallFrameHeaderSize> callFrame;
    for (int i = 0; i < RegisterFile::CallFrameHeaderSize; ++i)
        callFrame.append(newTemporary());

    emitExpressionInfo(divot, startOffset, endOffset);

#if ENABLE(JIT)
    m_codeBlock->addCallLinkInfo();
#endif

    emitOpcode(op_construct);
    instructions().append(dst->index()); // dst
    instructions().append(func->index()); // func
    instructions().append(argv.size()); // argCount
    instructions().append(argv[0]->index() + argv.size() + RegisterFile::CallFrameHeaderSize); // registerOffset
    instructions().append(funcProto->index()); // proto
    instructions().append(argv[0]->index()); // thisRegister

    emitOpcode(op_construct_verify);
    instructions().append(dst->index());
    instructions().append(argv[0]->index());

    if (m_shouldEmitProfileHooks) {
        emitOpcode(op_profile_did_call);
        instructions().append(func->index());
        
        if (dst == originalFunc)
            func->deref();
    }

    return dst;
}

RegisterID* BytecodeGenerator::emitPushScope(RegisterID* scope)
{
    ASSERT(scope->isTemporary());
    ControlFlowContext context;
    context.isFinallyBlock = false;
    m_scopeContextStack.append(context);
    m_dynamicScopeDepth++;

    return emitUnaryNoDstOp(op_push_scope, scope);
}

void BytecodeGenerator::emitPopScope()
{
    ASSERT(m_scopeContextStack.size());